PT - JOURNAL ARTICLE AU - Samuel Videholm AU - Thomas Wallby AU - Sven-Arne Silfverdal TI - Breastfeeding practice, breastfeeding policy and hospitalisations for infectious diseases in early and later childhood: a register-based study in Uppsala County, Sweden AID - 10.1136/bmjopen-2020-046583 DP - 2021 May 01 TA - BMJ Open PG - e046583 VI - 11 IP - 5 4099 - http://bmjopen.bmj.com/content/11/5/e046583.short 4100 - http://bmjopen.bmj.com/content/11/5/e046583.full SO - BMJ Open2021 May 01; 11 AB - Objective To examine the association between breastfeeding practice and hospitalisations for infectious diseases in early and later childhood, in particular, to compare exclusive breast feeding 4–5 months with exclusive breastfeeding 6 months or more. Thereby, provide evidence to inform breastfeeding policy.Design A register-based cohort study.Setting A cohort was created by combining the Swedish Medical Birth Register, the National Inpatient Register, the Cause of Death Register, the Total Population Register, the Longitudinal integration database for health insurance and labour market studies, with the Uppsala Preventive Child Health Care database.Patients 37 825 term and post-term singletons born to women who resided in Uppsala County (Sweden) between 1998 and 2010.Main outcome measures Number of hospitalisations for infectious diseases in early (<2 years) and later childhood (2–4 years).Results The risk of hospitalisations for infectious diseases decreased with duration of exclusive breastfeeding until 4 months of age. In early childhood, breast feeding was associated with a decreased risk of enteric and respiratory infections. In comparison with exclusive breast feeding 6 months or more, the strongest association was found between no breastfeeding and enteric infections (adjusted incidence rate ratios, aIRR 3.32 (95% CI 2.14 to 5.14)). In later childhood, breast feeding was associated with a lower risk of respiratory infections. In comparison with children exclusively breastfed 6 months or more, the highest risk was found in children who were not breastfed (aIRR 2.53 (95% CI 1.51 to 4.24)). The risk of hospitalisations for infectious diseases was comparable in children exclusively breastfed 4–5 months and children exclusively breastfed 6 months or more.Conclusions Our results support breastfeeding guidelines that recommend exclusive breastfeeding for at least 4 months.Data may be obtained from a third party and are not publicly available. We used deidentified register data obtained from third parties. It includes sensitive information and some access restrictions may apply. Interested researchers need to obtain data directly from the National Board of Health and Welfare in Sweden (socialstyrelsen@socialstyrelsen.se), from Statistics Sweden (scb@scb.se) and from the Child Health Service Unit in Uppsala (thomas.wallby@kbh.uu.se). Children included in the study were identified in the Medical Birth Register, data on hospitalisations were obtained from the Swedish National Patient Register and data on deaths were obtained from the Cause of Death Register. All of these registers are maintained by the National Board of Health and Welfare in Sweden. Data on maternal education were obtained from the Longitudinal Integration Database for Health Insurance and Labour market Studies and data on migration were obtained from The Total Population Register, both registers are maintained by Statistics Sweden. Data on breast feeding was obtained from The Child Health Care Quality database, which is maintained by the Child Health Service Unit in Uppsala.